Once you have a clone of the repository, you can just do a git pull at any time to update it to the most recent revision. See also UsingGit for more information, including information for people interested in contributing to MythTV development.

Please subscribe to the mythtv-dev mailing list if you plan to run development code! Instead of sending patches to the mythtv-dev mailing list for inclusion to MythTV, please create a ticket instead (TicketHowTo). This should allow us to track patches better, and hopefully get them handled in a much more timely manner (and avoid losing patches).